"I think, that in our eyes, it's obvious that the First World War changed the world.

"And [the war] was a moment of passage between the 19th Century and 20th Century, and was a beginning of modernity in a way. I think that the French people were not aware of the change brought by the First World War. Of course they could see a huge change that occurred in the rest of Europe, but that was in the countries who had lost the war.

"But French people didn't lose the war, so they couldn't change.

"That is the way the French society looked at itself after 1918, and it needed time for French people to consider that they couldn't escape the consequences of the war. It's only in the middle 20s that, for part of French society and especially the middle classes, people became aware that their century had changed completely."